Recording of a roundtable discussion session, sponsored by George Washington University's Medieval and Early Modern Studies Institute, mediated by Jeffrey J. Cohen, and held at the 47th International Congress on Medieval Studies (Kalamazoo, Michigan) on 11 May 2012. The roundtable features remarks by James Smith ("Fluid"), Alfred Siewers ("Trees"), Alan Montroso ("Human"), Eileen Joy ("Post/apocalyptic"), Anne Harris ("Hewn"), Lowell Duckert ("Recreation"), Carolyn Dinshaw ("Green"), and Valerie Allen ("Matter").